The rules of decorum from the 1940s and '50s were soundly rejected in the anti-establishment era of the '60s and '70s. We rudely pushed our way through the '80s as we followed the fast track. And now, we are pleased to announce that just before the end of the 1990s -- etiquette is back.

Helping to bring it back in well-appointed good taste is no less an authority than the great-granddaughter-in-law of Emily Post herself, Peggy Post.

Peggy Post, spokeswoman for the Post family, just completed the 16th edition of Emily Post's "Etiquette."

What makes Peggy Post such an authority?

Well, it's not just the fact that she married Emily's great-grandson, Allen Post, in 1979.

She had more than 20 years of experience in management, consulting and sales with companies like Chemical Bank and Merrill Lynch before she began learning the etiquette business from her mother-in-law, Elizabeth Post. Elizabeth was married to Emily's grandson, William.

Born in Washington, D.C., Peggy Post began her career as an international flight attendant for Pan American World Airways.

In 1991, she began making public appearances with Elizabeth at bridal shows, speaking engagements and media events.

Four years later she was named her mother-in-law's successor as spokeswoman for the Emily Post Institute, an entity established by Emily Post in 1946 and now maintained by her family to keep her name before the public.

Emily Post's "Etiquette The Blue Book of Social Usage," originally published in 1922, became the definitive guideline for how to properly handle almost every situation.

It's a safe bet, however, that in 1922, there were no sections addressing what color bridal gown an expectant mother should wear or how to talk to your date about his or her sexual history.

Those are issues tackled in the updated 75th anniversary guideline for living a well-mannered life in the '90s -- a decade in which Emily Post would have felt right at home.

The divorced mother of two sons, Emily Post had written three novels when she was approached by a book editor about writing an etiquette book.

"She thought it was an absolutely crazy idea," said Peggy Post.

Emily Post, who was 51 at the time, knew all the social graces, having grown up in Manhattan, the daughter of famous architect Bruce Price. Yet she researched the book for a year.

When the 700-page tome was published, it topped the best-seller list.

She went on to become the foremost authority on etiquette, hosting a radio program and writing a syndicated column that appeared in 150 newspapers across the country.

the time she died in 1960 at the age of 86, she had revised her book nine times.

More than just knowing what fork to use and how to address wedding invitations, "Etiquette," according to Peggy Post, "is a code of behavior based on thoughtfulness and consideration."

Two things almost everyone agrees we've not seen enough of in the past couple of decades.

The busy lifestyles of the two-career family don't leave much time for teaching social graces, Peggy Post said. Add the violence and profanity prevalent in television, music and movies, and she sees an American culture that has reached a crescendo of rudeness.

Now we are ready to play the music of life more softly and more civilly.

"Hopefully, our world and country are more interested in getting along with each other, and hopefully this book will help," she said.

In addition to the standard sections on how to set a formal or informal table, how to dress for the office and rules for introductions at social events, there are other decidedly '90s topics in the book.

For example, a chapter titled "Interrelationships" deals with issues involving divorced parents, live-in companions, au pairs, nannies and what to do if you've chosen to bear a child on your own.

On that last issue, the book states that until the child matures the mother should say, "Your daddy lives somewhere else." If the mother was artificially inseminated, she should heed the advice of counselors and tell the child, "I chose to have you because I wanted to love you and give you a happy life."

Another '90s dilemma -- videoconferencing -- is outlined in a chapter called "On the Job."

"It is important to avoid side conversations." Participants should also "make a point of glancing at the screen occasionally as it gives the appearance that you are making eye contact with those at the other site."

No update would be complete without a section on electronic communication.

For example, a business fax should be to the point, should not be confidential and should be neat and legible. The same goes for E-mail transmittals.

There are also rules for Internet etiquette, also known as netiquette.

The book states that "It is always a good idea, when entering any service or network, to take a few minutes and check the rules, regulations and any netiquette guidelines before beginning a conversation with anyone, entering a chat room or corresponding with an individual or a group."

It also includes the "Ten Commandments of Computer Ethics," among them "Thou shalt not copy software for which you have not paid," and "Thou shalt not snoop around in other people's files."